I have an HP 566 with installed windows 8. I removed them wanted to install windows 7.
I have problems installing win7.
In BIOS I can choose two boot modes:
1.Legacy boot mode
2.UEFI boot mode
If I chose the legacy boot mode for some strange reason all of my windows cd's stop booting at a certain point.
If I choose UEFI mode I enter the installation process but cannot install windows on the drives because they are GPT type. I tried converting them using diskpart. I get an error that disks cannot be converted.
How to proceed? I am really stuck here...
If it makes things easier also win XP can be installed :)
Windows locks its boot mode to its partition table type:
Therefore, if Windows complained that the disks were GPT, the installer was booted in BIOS mode, not in UEFI mode, no matter what boot mode you selected in the firmware. This can happen because some UEFIs use the boot mode you specify as more of a suggestion than a requirement; if you say "boot in UEFI mode," it'll try that, and if it can't, it will drop back to a BIOS-mode boot. My suspicion is that this is what's happened to you.
You could look for other firmware options related to the boot mode. Since the computer originally held Windows 8, chances are it had Secure Boot enabled, and that might explain the problem -- the firmware would try a Secure Boot with UEFI, fail, and then drop back to a BIOS-mode boot. (Really it shouldn't drop back to BIOS mode in that case, but I've seen other UEFIs do this.) If this hypothesis is correct, you may be able to fix the problem by going into your firmware and disabling Secure Boot. Unfortunately, the user interfaces vary so much that I can't say precisely how to do this; you'll just have to dig around until you find the appropriate option.
If that fails, you may need to tweak your installation medium, since they can be flaky on some computers. This can get a little tricky, but check the "Booting Windows Under DUET" section of this page. You can ignore the stuff on DUET (which is a way to run an EFI implementation as a sort of boot loader on a BIOS-based computer) and follow the numbered list for information on creating a bootable USB flash drive with the Windows installer. Copy the bootmgfw.efi file to EFI\BOOT\bootx64.efi to get it to boot automatically rather than manually selecting it, which DUET supports but your firmware might not.
I thought I'd finally relegated Windows to life inside a virtual machine, but alas, I came across some games I'd like to play that just won't do in that setup. In the days since Windows last occupied its own specified chunk of my disk I've done a lot of flipping around with different OSes and Linux distributions, and it turned out that while I had free space, I was at the maximum number of partitions supported by MBR partition tables. So, believing that it should Just Work® here in the 21st century and having performed a cursory examination of Google that indicated it should work, I converted over to a GUID partition table (GPT) and attempted to install Windows 7. Lo and behold, Windows 7 only works with GPTs on EFI systems, and mine uses BIOS. I should have noticed this in my earlier research, but that would have just been too easy.
So, I'm left with the choice of converting back to MBR and trying to jigger my partition layout around such that I can make one for Windows, or going with a hybrid MBR. The latter sounds more appealing. Unfortunately, there are lots of scary warnings about hybrid MBRs on the Internet, so I have a few questions.
Will Windows do something ugly to my bootloader since it's really on GPT but it will see MBR? Will that require more repair than booting from a LiveCD and running grub-install? Is there anything I need to avoid other than making sure I never touch partitioning tools on Windows? Will my computer explode? Would lots of headaches be saved if I just switched back to MBR? (I understand that Macs use hybrid MBRs with Boot Camp, so hopefully this won't be as difficult as I'm making it out to be.)
There are several possible solutions to this problem. To summarize, in more-or-less my order of preference:
I'd also like to clear up a couple of misconceptions:
There's no need to regress to the MBR partitioning scheme, nor even any need for a "hybrid MBR" partitioning scheme. (I have such on one of my machines, and attest that they are not for the fainthearted.)
Windows 7 can use EFI-partitioned discs just fine. It just cannot be bootstrapped from them on non-EFI machines, and (to protect you from yourself, in Microsoft fashion) refuses to install on them in the first place. In your case, your problem is a fundamental deficiency of your firmware, and isn't really a Windows issue at all. Your firmware doesn't understand the EFI partition table.
Such understanding is necessary if one wants to convert one's operating system bootstrap to be on EFI partitioned discs. One's firmware needs to know to put up the EFI Boot Manager menu, and then load the selected operating system loader program from the EFI System Partition. Your firmware isn't very smart, though, and doesn't know how to do much more than load the "master boot record" and run its bootstrap code. On an EFI partitioned disc there's no code in the "master boot record" to crank through the rest of the EFI boot process.
At best, right now, you have MBR bootstrap code that is equally as ignorant of the EFI partition table scheme as your firmware, and that's expecting to find and process an MBR partition table. What you need is two things:
The first is not impossible. There are two sources of such EFI-partitioning-aware MBR bootstraps:
Both will look for the "active" partition, and load and run its VBR, effectively bootstrapping in the old PC/AT and PC98 way but with an EFI partition table. Failing those two, the best alternatives that you'll get right now are:
The second (persuading Windows 7 to install on an EFI partitioned disc) is achievable, with the x86-64 flavour of Windows 7 at least. It's complex, not officially supported by Microsoft, and requires making what is effectively your own Windows installation disc with the EFI version of Microsoft's Boot Manager on it, and running that from within an EFI boot environment somehow. (If you have UEFI DUET installed, this is fairly easy, of course.) But it convinces Windows 7 that it its installer was bootstrapped on an EFI system, which criterion the installer uses to determine whether it will allow Windows to be installed on an EFI partitioned hard disc.
Of course, there's the additional, final, complexity of, once installed, bootstrapping Windows 7 from day to day; because the installer, knowing that you have EFI firmware, will have installed the EFI version of Microsoft's Boot Manager. You'll thus need either:
Pretty much all of this nonsense just goes away if one has EFI firmware in the first place. Windows 7 (x86-64) will install happily, and an EFI Boot Manager that understands the EFI partition table and that will load and run Microsoft's Boot Manager (as well as any other EFI-bootable operating system) directly from its ordinary program image file in the EFI System Partition, comes with the firmware.